feat: workspace aliases, tab groups of split panes, native path picker (v2.1.0)

- /api/workspaces and `agenthub workspace(s)` / `--workspace` as aliases of
  /api/lanes and `agenthub lanes` / `--lane`; old names print one stderr note.
  REPL `help lanes|workspace|workspaces` resolves through the aliases.
- A workspace holds up to ten sessions (slots 0-9); every console tab is a
  group of 1-4 split panes (PaneGroups, agenthub.workspace.paneLayout);
  parseGroups keeps the stored active tab when an earlier one is dropped.
- Browse button beside path fields: POST /api/lanes/pick-path opens the OS
  picker on the server's desktop — loopback only and no forwarding header
  (EREMOTE), a display failure is ENODIALOG not a Cancel, the dialog is
  killed when the request closes, a folder field falls back to the in-app
  browser on any failure.
- Changes rail counts chip, image viewer (/git/raw), status bar session
  counts and per-day cost (`date=` on /api/pricing/cost).
- /agenthub-open and /agenthub-doctor run from the INSTALLED build
  (supersededBy), doctor offers fixes behind two confirmations; plugin-open
  treats a locked bootstrap as non-fatal.
- New-terminal shell waits for the first attach (issue #55).
- repo-onboarding / debug-live-issue skills removed.
- OpenAPI: pick-path, lane/date on /pricing/cost, tool on /run/history,
  /api/workspaces mount.

server/__tests__/dashboard-runs.test.js

@@ -41,6 +41,17 @@ describe("dashboard-runs", () => {
     assert.ok(old.ended_at);
   });
 
+  it("narrows a lane's history to one tool", () => {
+    start("agenthub-lane-8", { laneId: 8, tool: "claude" });
+    start("agenthub-lane-8-1", { laneId: 8, tool: "shell" });
+    const shells = runs.listRuns({ laneId: 8, tool: "shell" });
+    assert.deepEqual(
+      shells.map((r) => r.id),
+      ["agenthub-lane-8-1"]
+    );
+    assert.equal(runs.listRuns({ laneId: 8 }).length, 2);
+  });
+
   it("flags as abandoned only the running rows whose pane is gone", () => {
     start("agenthub-lane-5", { laneId: 5 });
     start("agenthub-lane-6", { laneId: 6 });